http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52621
Richard Guenther <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |spop at gcc dot gnu.org --- Comment #10 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-04-05 11:27:02 UTC --- evolution_function_is_univariate_p returns true for {(integer(kind=8)) {0, +, {2, +, 2}_2}_2, +, 1}_3 but that does not look univariate to me - we do not properly look into CHREC_LEFT which is (integer(kind=8)) {0, +, {2, +, 2}_2}_2, so something like @@ -1114,6 +1132,8 @@ evolution_function_is_univariate_p (cons break; default: + if (tree_contains_chrecs (CHREC_LEFT (chrec), NULL)) + return false; break; } @@ -1127,6 +1147,8 @@ evolution_function_is_univariate_p (cons break; default: + if (tree_contains_chrecs (CHREC_RIGHT (chrec), NULL)) + return false; break; } fixes this. Then we ICE the same way in analyze_miv_subscript because we think that beast is affine-multivariate. The above fix looks obvious to me, but what the right condition for failing in analyze_overlapping_iterations should be for "loop_nest" should be, and why using the loop number of the outermost loop of the nest should be sufficient is beyond my understanding. Sebastian, can you help? I can certainly amend /* If they aren't the same, and aren't affine, we can't do anything yet. */ else if ((chrec_contains_symbols (chrec_a) || chrec_contains_symbols (chrec_b)) && (!evolution_function_is_affine_multivariate_p (chrec_a, lnn) || !evolution_function_is_affine_multivariate_p (chrec_b, lnn))) { dependence_stats.num_subscript_undetermined++; *overlap_iterations_a = conflict_fn_not_known (); *overlap_iterations_b = conflict_fn_not_known (); } though it looks to me that this should go into the else part and the analyze_miv_subscript case lacks a proper test.